1. Field of the Invention
This invention relates to a method for brightening the electrodeposits of zinc from alkaline zinc electroplating baths.
2. Description of the Prior Art
Various types of brightener additives for alkaline zinc electroplating process such as an organic aldehyde compound combining with a substituent, a ketone compound, a heterocyclic compound, a sulfur organic compound and/or a water-soluble high molecular compound have been widely investigated. These brightener additives which have been developed in the prior art are not satisfactory for use in a specific alkaline zinc electroplating bath such as the zincate or zinc cyanide baths, so far as workability and the plated zinc at the high current density are concerned.